Photographic shutter.



G. P. J. NISS.

PHOTOGRAPHIC SHUTTER. APPLICATION FILED OOT.19, 1908.

940,714. Patented N0v.23,1909.

2 BHEE'I'S-SHEET 1.

UNITED STATES PATENT QFFTCE.

CHRISTIAN F. J. NISS, OF CHICAGO, ILLINOIS.

PHOTOGRAPHIC SHUTTER.

T 0 all whom it may concern:

Be it known that I, CHRISTIAN F. J. NISS, a subject of the King ofDenmark, residing at Chicago, in the county of Cook and State ofIllinois, have invented a new and useful Photographic Shutter, of whichthe following is a specification.

This invention has reference to photographic shutters and moreparticularly of the type known as curtain shutters.

The object of the present invention is to provide a shutter of thecurtain type in which the speed materially exceeds that of curtainshutters of prior types.

As ordinarily made a curtain shutter consists of an opaque web arrangedto traverse the light beam either before or after entering the lens, theweb being provided with an opening as wide as the effective opening ofthe lens in a direction at right angles to the direction of travel ofthe web and usually adjustable as to width in the direction of travel ofthe web, the width of the opening or slit in the last named directiondetermining the higher speeds or shorter exposures of the sensitiveplates. Sometimes the curtain shutters are arranged close to the seirsitive surface of the plate when they are known as focal-plane shutters,but the pres ent invention relates more particularly to those shutterswhich are used immediately adjacent to the lens. It is to be understoodhowever that the invention is not necessarily limited to use inconnection with the lens only, but by suitable modification may be usedin the Vicinity of the sensitive film.

In accordance with the present invention, the opaque web is employedsimilar to the curtain shutters of prior construction, but the opaqueweb is made in two coacting parts each of which is provided with a slitor openings which may be made large or small as desired and these twoopenings are made to pass in opposite directions transverse to thelongitudinal axis of the lens, one in front of the lens and the otherbehind the same and both in close relation to the said lens.

In accordance with the present invention the web is made continuous andis passed about an actuating roller which latter is caused to rotate bya spring put under tension at the will of the operator and in order thatthe size of the opening may be adjusted at will the web is made up oftwo members each in the form of an endless band and one Specification ofLetters Patent.

Application filed. October 19, 1908.

Patented Nov. 23, 1909.

Serial No. 458,415.

interior to the other and in close relation thereto and these two bandsare capable of relative longitudinal adjustment so that the openingstherethrough may be made large or small in effective size. Provision isalso made by the present invention for the placing of the shutter insuch relation to the camera box or to the plate that the direction ofmovement oft-he openings or slits, and especially the outer opening orslit may be the same as the direction of movement of the object to bephotographed, or if desired in the reverse direction.

The invention will be best understood from a consideration of thefollowing detail description taken in connection with the accompanyingdrawing forming a part of this specification, in which drawing Figure 1is a plan view of the shutter as applied to a camera front. Fig. 2 is asimilar view with the top removed and some parts broken away. Fig. 3 isa perspective view of the curtain with the two parts thereof in displaced relation. Fig. 1 is a side elevation of the shutter as applied toa camera front. Fig. 5 is a longitudinal vertical section through thestructure shown in Fig. 4 with the camera front omitted. Fig. 6 is adetail view showing a means for locking one of the rollers in place.

Referring to the drawings there is shown a camera bellows 1 terminatingin the usual front board 2, and there is also shown a photographic lens3 which may be taken as of any ordinary or approved construction.

The working parts of the shutter are inclosed in a suitable box or case4, and the bottom 5 of this box is hinged to the back thereof while thefront 6 of the box is hinged to the bottom 5, the usual clips 7 beingused to hold the front 6 and bottom 5 in place. The front 6 is providedwith an opening 8 in line with the front of the lens 3.

The lens 3 is made fast to the lens board 9 in the usual manner and thislens board 9 is removably secured in the front of a supplemental chamber10 in the manner usually employed for fastening lens boards to thefronts of camera boxes.

Secured to the back of the box 4 is a sleeve or barrel 11 which isexternally screw-threaded and receives a clamp ring 12 designed toengage the front 2 of the camera body while the sleeve or barrel 11extends through the usual opening in the front of the camera -'body,that is through the front board 2 and another clamp ring 13 applied tothe sleeve 11 serves to clamp the barrel 11 firmly to the front board 2but in such manner that the said barrel may be turned on its centrallongitudinal axis for a purpose which will hereinafter appear.

Within the box f at one side of the lens there is mounted a drum orroller 11 having near each end radially projecting pins and also nearone end other pins 16 the purpose of which will hereinafter appear.

On the side of the lens remote from the roller let are other two spacedrollers 17 and 18 smaller than the roller let and mounted in suitablebrackets 19. The rollers 17 and 18 are spaced apart in a directionparallel with the optical axis of the lens and the roller 18 has one ofits journals mounted in a recess 20 formed in the corresponding end ofthe bracket 19 and a sliding plate 21 is mounted 011 the bracket and isunder the control of suitable clamp screws so that the plate may beadjusted longitudinally and then clamped in place. One end of the plate21 is provided with a finger 23 arranged to traverse the slot- 20 so toengage and hold the corresponding journal of the roller 18 in the slotor recess 20 when so desired. The finger 23 may be moved out of the pathof the journal of the roller 18 so that the latter may be removed fromthe corresponding bracket 19 for a purpose which will pres ently appear.

The rollers 14L, 1'7 and 18 form the support for a curtain 2 1 in theform of a continuous web of proper width. The curtain web 24 is carriedabout the roller 14-. and past the front of the lens then about therollers 18 and 17 in order and then back of the lens through the chamber10 which may have its ends open for the passage of said web or curtain.The curtain is provided along one portion at the top and bottom withperforations 25 and the cloth about these perforations may be protectedby suitable eyelets, it being customary to make the curtain or web ofrubber cloth both because of its flexibility and its opacity. Theperforations 25 are entered by the pins 15 on the roller ll and thesepins cause the curtain to participate in any movement of the said roller14. Since the extent of travel of the curtain need only be slightlygreater than the diameter of the lens, and since the roller 14: is, ormay be, of a diameter substantially the length of the lens, it followsthat but a few pins and perforations are needed.

The curtain or web 2 1 is made up of two members 26 and 27 one interiorto the other and each provided with openings 28 and 29, the openings 28of each web matching the openings 28 of the other web, and the samebeing true with the openings 29. The location of the openings 28 and 29is such that the openings 28 are located in the run of the curtain orweb at the front of the lens, and the openings 29 are in the run of thecurtain or web at the back of the lens.

()ne of the journals 30 of the roller or drum 1 f is continued upwardthrough the top of the box 5 and there carries a manipulating button orthumb wheel 31 while between the top of the roller ll and the under sideof the top of the box atthe journal 30 carries a winding drum 32 towhich is made fast a strand 38 which latter in turn is secured to aspring 3% shown in the drawings as a helical spring. The other end ofthis spring 3st is made fast to a slide 35 capable of movement alongguides 36 on the under face of the top of the box and this slide carriesa pin 37 projecting up through a slot 38 in the top of the box. The pin37 carries a snap member 39, or the pin itself may be made elastic so asto engage in spaced recesses etO along one side of the slot 88. Thestructure just described constitutes a convenient means for locking theslide in any desired position along the slot 38 so that the spring 34Lmay be put under a greater or less tension as desired by the operator.it will be understood of course that any other suitable means for thepurpose may be em ployed.

Fast on the fixed portion of the structure, say on top of the walls ofthe chamber 10, there is pivoted a lever il having one end 4L2 in thepath of the pins 16 projecting from the drum let. The other end 13 ofthe lever ll is bent to project up through the top of the box at througha slotet t therein provided for the purpose and the extent of projectionis sufficient for the easy movement of the lever by the finger of theoperator. A spring 45 engaging the lever 11 serves to constrain it to aposition where its end 42 will be in the path of the pins 10.

lVhen it is desired to expose a photographic plate with the shutterdescribed the roller or drum 14L is first turned in a direction to putthe spring 3st under the maximmn tension for the exposure desired, thedegree of tension being adjustable by moving the slide 35 so that thecatch 3.) is in the desired one of the notches 410 for the speed wanted.

When the drum 14 has been turned by proper manipulation of the thumbpiece or button 31 the said roller or drum 1+ is retained in the setposition by means of the engagement of one of the pins 1t) with the end%2 of the lever 41. Under these circumstances the openings 28 throughthe curtain are, in the particular structure shown, and in the positionof parts shown in Fig. 2, to the left of the front of the lens as viewedin said figure, while the openings 29 are to the right of the rear ofthe lens as viewed in said figure, and both openings are so located thatno light will pass through the lens and reach the photographic plate. If110w the lever 41 be moved in a direction to carry the head 42 out ofthe path of the pin 16 with which it is in engagement when the shutteris set for operation, the roller 14 will be released to the action ofthe spring 34 and will be caused to rotate thereby and the engagement ofthe pins 15 in the perforations 25 will cause participation in thismovement of the curtain or web 24 and the openings 28 and 29 are thencarried in 0pposite directions across the front and back of the lensrespectively.

The two pins 16 may be so spaced that when the roller 14 is released bymoving the head 42 out of the path of one pin it may be then engaged bythe other pin. The spacing of the pins 16 may be such that the secondpin in order of active rotation of the roller 14 will by engagement withthe head 42 hold the roller in a position where the openings 28 and 29are in the optical axis of the lens in which case the structure is setfor time exposures.

If it be desired to change the elfective size of the openings 28 and 29then the slide 21 is moved so that the finger 23 is out of the path ofthe pintle or journal of the roller 18 and the latter may be lifted fromits support thus loosening up the web or curtain 24. Now the two membersof the curtain may be moved one on the other until the openings 28 and29, if initially. fully coincident may be moved one relative to theother so that the effective opening is narrowed to the desired extent,or if the initial position be some intermediate position then theopening may be made larger or smaller as desired. Then by replacing theroller 18 and locking the same in place the curtain is again stretchedto its original tautness.

By means of the connecting clamp rings 12 and 13 the shutter is soattached to the front board 2 of the camera body that it may be turnedabout an axis coincident with the optical axis of the lens. By thismeans the direction of movement of the curtain may be made the same asthe direction of movement of the object to be photographed, whether thatdirection be horizontal, or vertical, or at any angle to either.

Focal plane shutters are provided with adjustable slits which admit of awide range of speeds of exposure with the same speed of the curtain andthe speed of the latter may also be varied within limits, but in thecase of the focal plane shutter the exposure opening must pass along thefull length of the plate, and in the larger sizes of plates in commonuse this distance is considerable. lVhile with the focal plane shutter,the extent of exposure is substantially that of the slit or opening inthe curtain, structural limitations prevent a greater speed of exposurethan about one one-thousandth of a. second.

Ithas been proposed to use curtain shutters in connection with lenseseither in front of or behind the lens or between the lens system, butsuch shutters as heretofore constructed do not prevent a diffusion oflight over the plate and the consequent cutting down of the speed ofexposure even though, because of the small size of the curtain and itslightness its actual speed may be great as compared with the speed ofthe curtain of the focal plane structure.

Vith the present invention a beam of light is admitted to the lensthrough the slit in the curtain, and this beam of light if unaffectedother than by the lens would spread out to a marked extent over theplate located in the focus of the lens, and therefore the actual surfaceexposed to the action of light would be much greater than is the casewith the focal plane shutter. Therefore even though the actual speed ofthe shutter be greater than is the case with the focal plane shutter,the time that any portion of the plate is exposed to the light ismaterially greater than in the case of the focal plane shutter. lViththe present invention however this objectionable feature is eliminatedby the use of the second opening back of the lens moving in a directionopposite to that of the first opening and so cutting off marginal raysof light and restricting the beam of light reaching the plate to anarrow band which sweeps across the same with a speed depending on thesize of the plate, the distance of the same from the lens, and theactual speed of the curtain.

By using narrow slits in the curtain and setting the same at high actualspeed, an exposure approaching one twenty five hundredth part of asecond has been obtained and photographs taken at such high speed havebeen successfully recorded on ultrasensitive plates.

Because of the lightness and simplicity of the oppositely acting curtainshutter of the present invention it is possible to obtain exposures oftoo great a rapidity to be recorded on photo-sensitive plates of eventhe most sensitive character now obtainable.

What is claimed is 1. A photographic shutter having openings for thepassage of light movable across the optical axis of the lenssimultaneously in opposite directions, said openings being adjustable asto their effective size for the passage of light therethrough.

2. A photographic shutter having spaced openings for the passage oflight movable across the lens simultaneously in opposite directions,said openings being adjustable simultaneously as to their effective sizefor the passage of light therethrough.

3. A photographic shutter having spaced openings for the passage oflight separated in the direction of the optical axis of a lens andmovable across said optical axis simultaneously in opposite directions,said shutter having two members adjustable one on the other to determinethe size of the free openings through the shutter.

l. A photographic shutter having openings for the passage of light, oneopening being movable across the optical axis of a lens in front of thelatter and another opening being movable across the optical axis of thelens behind the latter, the movement of the openings across the opticalaxis of the lens being simultaneous and in opposite directions.

A photographic shutter having openings for the passage of light spacedapart in the direction of the optical axis of the photographic lens, andmeans for adjusting the effective size of the openings.

(3. A photographic shutter having openings for the passage of lightmovable across the optical axis of a lens simultaneously in oppositedirections, said openings being adjustable as to width in the directionof movement.

7. A photographic shutter having an endless curtain with oppositelydirected runs, in each of which there is formed an opening for thepassage of light, the said openings coacting, and means forsimultaneously adjusting the size of the openings to the same extent.

8. A photographic shutter having an endless curtain with oppositelydirected runs in each of which there is formed an opening for thepassage of light, the said openings coacting, and means for supportingthe curtain with the runs on opposite ends of a photographic lens.

9. A photographic shutter having an endless curtain with oppositelydirected runs through each of which there is formed an opening for thepassage of light,the said openings coacting and being adjustable as towidth in the direction of travel of the curtain.

10. A photographic shutter having an endless curtain formed of twomembers movable longitudinally one on the other and each having twoopenings matching the openings on the other, the said curtain having thematching openings in its two members located in oppositely directedruns.

11. A photographic shutter having an endless curtain formed of twomembers one within the other and movable longitudinally one on the othersaid members each having two separated openings with the openings in onemember matching the openings in the other member, a spring actuateddriving roller engaging said curtain and other support-ing and guidingrollers for the curtain one of which rollers is removable.

12. A photographic curtain shutter adj ustable about the optical axis ofthe photographic lens, and means for locking the shutter in adjustedpositions.

18. A photographic shutter comprising a suitable carrier, an endlesscurtain therein having opposite runs with coacting passages for lighttherethrough, means for supporting a lens between the runs of thecurtain, and means for attaching the shutter to the front of a camerabody.

1%. A photographic shutter having an endless curtain formed of twomembers movable longitudinally one on the other and each having twoopenings matching the openings of the other, with the matching openingslocated in oppositely directed runs, and a power actuated roller aroundwhich both members are passed and about which they are relativelyadjustable to determine the size of the free openings through thecurtain.

15. A photographic shutter having an endless curtain formed of twomembers having relative adjustments one on the other and each having twoopenings matching the openings of the other with the matching openingslocated in oppositely directed runs, means for causing the simultaneousmovement of the two members of the curtain and means for permitting therelative adjustment of the two members of the curtain in the directionof the length thereof.

16. A photographic shutter having an endless curtain formed of twomembers each having two openings matching the openings of the other withthe matching openings located in oppositely directed runs and eachmember of the curtain having a series of perforations, and a poweractuated roller around which both members are passed, said roller havingradially projecting pins for engaging the series of perforations in thetwo members of the curtain.

17. In a photographic shutter having an endless curtain formed of twomembers each having two openings matching the openings of the other withthe matching openings located in oppositely directed runs and eachmember being provided with a series of perforations, a roller havingprojecting pins adapted to extend through both series of perforations inthe two members of the curtain and to thereby hold the two members inrelatively adjusted positions, and means for holding the curtain membersto the said roller and for permitting the release of the said membersfrom the said roller for relative longitudinal adjustment one on theother.

In testimony that I claim the foregoing as my own, I have hereto afiixedmy signature in the presence of two witnesses.

CHRISTIAN F. J. NISS. lVitnesses ANNA A. Bowman, N. P. OSTED.

